1. Field of the Invention
This invention relates to a tablet input device with a switch. More particularly, this invention relates to a tablet input device with a switch capable of controlling the movements of a cursor, a pointer, etc. in accordance with an operating direction and additionally integrated with a deterministic switch for determining positions of the cursor, the pointer, etc.
2. Description of the Background Art
A cursor or a pointer showing a designating position must be able to be smoothly moved on a display such as a personal computer, etc., and a switch must be able to be pushed and inputted in a predetermined moved position. It is desirable to move the cursor or the pointer and input the switch by a series of operations. Therefore, the applicant already proposed xe2x80x9ca tablet input device with a switchxe2x80x9d (Japanese Patent Application No. 348716 in 1998 as an input device of this kind. The tablet input device with a switch (Japanese Patent Application No. 348716 in 1998) will next be explained on the basis of FIGS. 10 and 11.
In this tablet input device with a switch, as shown in FIGS. 10 and 11 as assembly views, tablet sheets 106a, 106b as a pair are spaced from each other at a slight distance and are arranged in parallel with each other. An operating button 102 is arranged on the tablet sheets 106a, 106b. A bottom face 102b of the operating button 102 is formed in a spherical crown shape and an operating portion 102a is formed on an upper face of the operating button 102. The operating button 102 and the tablet sheets 106 are stored to a tablet case 105 such that the operating portion 102a faces outward and the operating button 102 is freely rolled on the tablet sheets 106. The tablet case 105 storing the operating button 102 and the tablet sheets 106 in this way is supported and located between an attaching plate 108 for cantilevering a leaf spring piece 107 and the inner face of an outer case 111 having an opening 111a bored such that the operating portion 102a formed in the operating button 102 faces further outward. A pushbutton switch 113 is arranged inside the leaf spring piece 107 or the tablet case 105 and an actuator 113a is arranged in the pushbutton switch 113.
In the tablet input device 101 with the switch formed in this way, the bottom face 102b formed in a spherical crown shape is rolled on the tablet sheets 106 by operating the operating portion 102a of the operating button 102 and is pressed in a position shifted from a center of the operating button 102. The tablet sheets 106a and 106b then come in contact with each other in a rolling position. Output data showing a shift operating amount from the center of the operating button 102 are outputted from the contact position of the tablet sheets 106a and 106b. 
Further, the operating button 102 is pressed against elastic force of the leaf spring piece 107 with pressing force equal to or greater than a predetermined value in a contact state of the tablet sheets 106a and 106b. Thus, the actuator 113a is pushed down by the leaf spring piece 107 or the tablet case 105 and the pushbutton switch 113 is operated.
Thus, in the conventional example, the shift operating, amount in the rolling position is outputted by rolling the operating button 102 and the operating button 102 is pressed by further strengthening the pressing force in this position so that the actuator 113a is pushed down and the pushbutton switch 113 can be operated. However, in this tablet input device with the switch, the pressing force for pressing the actuator 113a becomes pressing force equal to or greater than a predetermined value and resisting elasticity of the leaf spring piece 107, but the actuator 113a is pressed in a shifting position in which the operating button 102 is rolled. Accordingly, a distance from a cantilever position of the leaf spring piece 107 to a pressing force point on the leaf spring piece 107 is changed in accordance with the shifting position. Therefore, a problem exists in that the pressing force for pressing the actuator 113a is different in accordance with the shifting position. Namely, when the actuator 113a is pressed on a side close to the attaching plate 108 in the cantilever position of the leaf spring piece 107, stronger pressing force is required in comparison with a case in which the actuator 113a is pressed on a side far from the attaching plate 108 (i.e., a side close to the actuator 113a). Thus, a problem exists in that the pressing force is different in accordance with the shifting position for pressing the actuator 113a. Further, a supporting portion 108a for cantilevering the leaf spring piece 107 is indispensable. It is necessary to fix the supporting portion 108a to the outer case 111 in a position. shifted from at least the tablet case 105. Therefore, for example, when the supporting portion 108a is fixed to a portion in which there is no sufficient mounting space as in a remote controller, a problem exists in that the arrangement of switches, etc. arranged on a surface of the outer case 111 is limited.
In consideration of the above problems, an object of this invention is to provide a tablet input device with a switch in which no pressing force for pressing an actuator depends on a shifting position of an operating button and an attaching space to an outer case is reduced.
Therefore, this invention provides a tablet input device with a switch comprising:
a tablet sheet constructed by upper and lower sheets arranged such that surfaces of the upper and lower sheets are oppositely spaced from each other;
an operating button arranged on the tablet sheet such that a bottom face coming in contact with the tablet sheet is formed and an operating portion is formed on a surface of the operating button;
a tablet case in which an outer frame is formed around a bottom portion formed in a plate shape and the operating button and the tablet sheet are opposed to each other so as to freely roll the bottom face of the operating button on the tablet sheet, and the operating portion of the operating button faces. outward and is stored into the outer frame;
an outer case in which an opening for making the operating portion of the operating button face outward is bored;
a substrate set such that the tablet case is nipped and oppositely arranged between the substrate and the outer case;
a pushbutton switch arranged on a substrate surface opposed to the opening bored in the outer case and having an actuator arranged on an opening side; and
an elastic leg body in which a basic end portion is fixed to an outside face of the outer frame arranged in the tablet case and a first leg body slantingly extends from the basic end portion to a substrate side, and a second leg body crosses the first leg body in an X-shape and has a basic end portion slidably engaged along an outside face of the outer frame of the tablet case and is rotatable with respect to the first leg body with a crossing portion as a center, and the first and second leg bodies are respectively arranged on opposite sides of the outer frame;
the tablet input device being constructed such that:
the operating portion of the operating button is shifted from its center and is pressed and operated, and the upper and lower sheets come in contact with the bottom face of the operating button in a shifting position so that the tablet sheet outputs output data showing a shift operating amount from the contact position; and
the operating portion of the operating button is pressed by pressing force resisting elastic force of the elastic leg body, and the bottom portion of the tablet case pushes down the actuator of the pushbutton switch so that the pushbutton switch is operated.
In an operation of this invention, when the operating portion of the operating button is operated in a position shifted from the center, the bottom face of the operating button is rolled and the upper and lower sheets of the tablet sheet come in contact with each other in the shifting position. The tablet sheet outputs output data showing a shift operating amount from the shifting contact position.
When the operating portion of the operating button is pressed by pressing force stronger than the elastic force of the elastic leg portion, the X-shape of the crossing elastic leg body is deformed and the tablet case is moved in parallel and pushes down the actuator of the pushbutton switch arranged on the substrate so that the pushbutton switch is operated.